Add responsiveness for footer. Update gulpjs, package.json and bootstrap sass

static/assets/bootstrap/sass/utilities/_borders.sass

@@ -0,0 +1,71 @@
+// stylelint-disable declaration-no-important
+
+//
+// Border
+//
+
+.border
+  border: $border-width solid $border-color !important
+
+.border-top
+  border-top: $border-width solid $border-color !important
+
+.border-right
+  border-right: $border-width solid $border-color !important
+
+.border-bottom
+  border-bottom: $border-width solid $border-color !important
+
+.border-left
+  border-left: $border-width solid $border-color !important
+
+.border-0
+  border: 0 !important
+
+.border-top-0
+  border-top: 0 !important
+
+.border-right-0
+  border-right: 0 !important
+
+.border-bottom-0
+  border-bottom: 0 !important
+
+.border-left-0
+  border-left: 0 !important
+
+@each $color, $value in $theme-colors
+  .border-#{$color}
+    border-color: $value !important
+
+.border-white
+  border-color: $white !important
+
+//
+// Border-radius
+//
+
+.rounded
+  border-radius: $border-radius !important
+
+.rounded-top
+  border-top-left-radius: $border-radius !important
+  border-top-right-radius: $border-radius !important
+
+.rounded-right
+  border-top-right-radius: $border-radius !important
+  border-bottom-right-radius: $border-radius !important
+
+.rounded-bottom
+  border-bottom-right-radius: $border-radius !important
+  border-bottom-left-radius: $border-radius !important
+
+.rounded-left
+  border-top-left-radius: $border-radius !important
+  border-bottom-left-radius: $border-radius !important
+
+.rounded-circle
+  border-radius: 50% !important
+
+.rounded-0
+  border-radius: 0 !important